1. Field of the Invention
This invention relates to ratchet drive devices, and more particularly, to a ratchet wrench which is characterized by top and bottom handles fixedly attached to, or shaped integrally with separate housing elements to achieve a mechanical advantage in driving a socket drive extending from the bottom housing element. The split housing encloses a cylindrically shaped, hollow ratchet drum having vertically oriented, external splines and rotatably situated in the housing. The ratchet drum contains a pair of oppositely-disposed side bevel gears rotatably mounted on a horizontal shaft fixedly mounted inside the ratchet drum, and a top bevel gear is attached to the inside of the top housing element, and extends inside the ratchet drum to engage the side bevel gears on the shaft. Similarly, a drive bevel gear rotatably engages the side bevel gears at a point on the lower housing element opposite the top bevel gear, and carries a socket drive which extends from the drive bevel gear through the lower housing element to receive a socket. The respective handles and housing elements are rotatable with respect to the ratchet drum, and are designed to drive the ratchet drum and the socket drive in a desired direction by means of a top and bottom ratchet, attached to the top and bottom handles, respectively, depending upon the relative position of ratchet pawls in engagement with the ratchet drum splines. For example, adjustment of the ratchet pawls for engagement in a common first position in the top and bottom ratchet, respectively, facilitates rapid rotation of the socket drive in a clockwise direction when the top and bottom handles are alternately rotated in opposite directions. Conversely, when the ratchet pawls are moved into a common second position in the top and bottom ratchet, rotation of the handles in opposite directions facilitates movement of the socket drive in the counter-clockwise direction. Furthermore, with the ratchet pawls adjusted in a first common engaged position in the top and bottom ratchets, respectively, and the top and bottom handles held or locked together in parallel fashion, the ratchet wrench can be used as a conventional ratchet wrench, and movement of the top and bottom handles in concert against the locked ratchet pawls drives the socket drive in a selected direction. Conversely, adjustment of the ratchet pawls in a second common direction and maintaining the top and bottom handles in alignment while rotating the handles in the opposite direction effects a rotation of the socket drive in that opposite direction. In a preferred embodiment of the invention the top and bottom handle can be secured to act in concert or released for manipulation in different directions by means of a handle lock which cooperates with the top and bottom handles.
2. Description of the Prior Art
Devices for driving bolts, lag screws and other fastening devices having heads suited for manipulation by sockets are well known in the prior art. Such devices include single and double-head wrenches, box and open end wrenches and similar tools. More sophisticated wrenches having a ratcheting function were developed to solve the problem of installing bolts and nuts and other fasteners having a square or hexagonal head configuration in cramped locations, such as in or near engines and machinery, where a conventional wrench cannot be engaged and operated in a complete circle or in a substantial arc without contacting other parts of the machine. In such application, conventional wrenches must be first engaged with the nut or bolt head, rotated to the extent possible to tighten or loosen the nut or bolt, and repositioned for another sequence. The conventional ratchet wrench allows the user to adjust the ratchet pawl in the drive drum splines to achieve clockwise or counter-clockwise driving of the socket drive and return of the wrench handle to the initial placement position by operation of the ratchet. Such ratchet drive devices are available in a variety of sizes, and are highly useful in tightening and loosening nuts and bolts.
An improved ratchet wrench is disclosed in U.S. Pat. No. 1,860,914, to Henry J. Wellman, which device includes a dual handle ratchet mechanism which uses a common, splined ratchet drum having interior bevel gears which mesh to provide a gear box for driving a socket drive when the handles are rotated with respect to each other.
It is an object of this invention to provide a new and improved, dual handle ratchet wrench which is characterized by a split housing, an interior ratchet drum provided with internal bevel gears and exterior splines, a pair of ratchet mechanisms on the handles for selectively engaging the splines on the ratchet drum, and a handle lock for securing the handles together and operating the wrench in conventional fashion in one embodiment, and allowing the handles to be separately manipulated, in another, more efficient embodiment of the invention.
Another object of this invention is to provide a new and improved ratchet wrench which is provided with a split housing, a top arm carried by the top housing segment of the split housing and a bottom arm cooperating with the bottom housing segment of the split housing, the arms also provided with separate ratchet mechanisms for selectively engaging a splined ratchet drum rotatably positioned inside the split housing and carrying a pair of oppositely-disposed side bevel gears rotatably mounted on a horizontal shaft secured to the ratchet drum, the top housing segment further carrying a top bevel gear which meshes with the side bevel gears, and a drive bevel gear rotatably cooperating with the bottom housing segment and also meshing with the side bevel gears and having a socket drive extending from the bottom housing, the side bevel gears and ratchet drum cooperating with the handles to effect a clockwise or counter-clockwise rotation of the socket drive when the ratchet mechanisms are in a selected first or second position, and the handles are manipulated away from each other and toward each other in sequence.
Still another object of the invention is to provide a ratchet wrench having a pair of housing segments joined by a split ring, and dual handles cooperating with the respective housing segments, and a ratchet means in each handle, the ratchet wrench further provided with a ratchet drum having four cooperating bevel gears in the interior thereof, the bottom one of the bevel gears carrying a socket drive extending outside the lower housing, and a handle lock means for selectively securing the handles together and operating the ratchet wrench in conventional fashion in one embodiment, and manipulating the handles both toward and away from each other for each selected position of the ratchet means on each handle, to drive the socket drive in either direction, in another, more efficient embodiment of the invention.